Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit cb395eaf authored by Anatolij Gustschin's avatar Anatolij Gustschin Committed by David S. Miller
Browse files

fs_enet: add FEC TX buffer alignment workaround for MPC5121 



MPC5121 FEC requeries 4-byte alignmnent for TX data buffers.
This patch is a work around that copies misaligned tx packets
to an aligned skb before sending.

Signed-off-by: default avatarJohn Rigby <jcrigby@gmail.com>
Signed-off-by: default avatarPiotr Ziecik <kosmo@semihalf.com>
Signed-off-by: default avatarWolfgang Denk <wd@denx.de>
Signed-off-by: default avatarAnatolij Gustschin <agust@denx.de>
Acked-by: default avatarGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 60ab4361

drivers/net/fs_enet/fs_enet-main.c

+47 −0
Original line number Diff line number Diff line
@@ -580,6 +580,40 @@ void fs_cleanup_bds(struct net_device *dev) 


/**********************************************************************************/



#ifdef CONFIG_FS_ENET_MPC5121_FEC

/*

 * MPC5121 FEC requeries 4-byte alignment for TX data buffer!

 */

static struct sk_buff *tx_skb_align_workaround(struct net_device *dev,

					       struct sk_buff *skb)

{

	struct sk_buff *new_skb;

	struct fs_enet_private *fep = netdev_priv(dev);



	/* Alloc new skb */

	new_skb = dev_alloc_skb(skb->len + 4);

	if (!new_skb) {

		if (net_ratelimit()) {

			dev_warn(fep->dev,

				 "Memory squeeze, dropping tx packet.\n");

		}

		return NULL;

	}



	/* Make sure new skb is properly aligned */

	skb_align(new_skb, 4);



	/* Copy data to new skb ... */

	skb_copy_from_linear_data(skb, new_skb->data, skb->len);

	skb_put(new_skb, skb->len);



	/* ... and free an old one */

	dev_kfree_skb_any(skb);



	return new_skb;

}

#endif



static int fs_enet_start_xmit(struct sk_buff *skb, struct net_device *dev)

{

	struct fs_enet_private *fep = netdev_priv(dev);
@@ -588,6 +622,19 @@ static int fs_enet_start_xmit(struct sk_buff *skb, struct net_device *dev) 
	u16 sc;

	unsigned long flags;



#ifdef CONFIG_FS_ENET_MPC5121_FEC

	if (((unsigned long)skb->data) & 0x3) {

		skb = tx_skb_align_workaround(dev, skb);

		if (!skb) {

			/*

			 * We have lost packet due to memory allocation error

			 * in tx_skb_align_workaround(). Hopefully original

			 * skb is still valid, so try transmit it later.

			 */

			return NETDEV_TX_BUSY;

		}

	}

#endif

	spin_lock_irqsave(&fep->tx_lock, flags);



	/*